In FY 2014, we continued the investigation of the staphylococcal peptide cytolysins, phenol-soluble modulins (PSMs). Current efforts focus on the contribution of PSMs to different infection types and the role of allelic variants of PSMs in defining pathogenesis. Furthermore, we are continuing our efforts to define the mechanism of the PSM exporter with the ultimate goal of targeting the exporter for drug development. In collaboration with Dr. Fowler at Duke, we have determined that PSM production is correlated with skin infections, representing one of the very few available findings providing epidemiological evidence for the importance of PSMs in S. aureus pathogenesis. We are also emphasizing our investigation of global lineages of hospital- and community-associated MRSA strains and of the factors that define their pathogenic and epidemiological success. These endeavors are conducted predominantly with collaborators in China and Brazil.